Inclosed fuse.



E. H. GILBERT.

INCLOSED FUSE.

APPLICATION FILED IIAv I. 1913.

wITNEssEs: A NvENToII y I BY .. W11. 0&3. l i WMI/mow UNITED STATES PATENT OFFICE.

EDWIN H` GILBERT, OF WILKINSBURG. PENNSYLVANIA, ASSIGNOR T0 WESTINGHOUSE ELECTRIC & MANUFACTURING COMPANY, A CORPORATION OF PENNSYLVANIA.

INCLOSED FUSE.

Specication of Letters Patent.

Patented Nov. 13,1917.

Application led May 1, 1913. Serial No. 764,804.

To all 'ur/wm it may concern:

Be it known that I, EDWIN H. GILBERT, a citizen of the United States, and a'resident of Wilkinsburn, in the county of Allegheny and State of ennsylvania, have invented a new and useful Improvement in Inclosed Fuses, of which the following is a specification.

My invention relates to protective devices for electrical circuits and it has special reference to inclosed fuses of the renewable type.

The object of my invention is to provide a reliable andV inexpensive inclosed fuse which'shallibe adapted to convenient renewal and shall embody means `for visibly and plainly disclosing the condition thereof.

Heretofore, many inclosed fuses have been more or less troublesome to renew by reason of the filling material or incombustiblepowder which was 'allowed to remain loosely in the casing. The indicationot` the condition of the fuse was also not so plain as might be desired. Moreover, it was possible to substitute a fuse of different rating from that specified as proper for the particular circuit.

According to my invention, I provide an incasing member and a renewable element adapted for insertion therein and comprising a cartridge containing both the fuse and the powder, thereby making the renewal of a burned-out fuse very convenient and rapid. In addition, the cartridge has one portion reduced in size-and a paperband is partially attached thereto. Upon rupture of the fuse, the reduced portion expands and bursts the paper, thereby plainly disclosing the condition ofthe fuse. Inspection of the paper band, upon which' are printed the voltage and current ratings of the inclosed fuse, is permitted by means of a small window of glass or other suitable material disposed in the outer casing opposite the printed ratings. It will be understood that the rating figures cannot be'altered without destroying the paper band. Moreover, substitution of a fuse having a capacity larger than that specified as proper for the particular service conditions maybe immediately detected upon inspection.

In the accompanying drawings, Figure 1 is a view,mainly in' longitudinal section but partially in elevation, ofa complete proteclongitudinal elevation of a complete protective device embodying my invention and employmg a modified formof the acces- ,sories thereto; Fig. G is a partial View in longitudinal section taken at rightangles to the view of Fig. 5; and Fig. 7. is a Sectionalfview, on the line AVII-#VII of .-Fig. 6,all sectional views being taken as looking in theA direction Iof the correspondinglar- IOWS. l I Y' Referring to the drawing, a protective device 1 `for electric-circuits comprises an outer casing 2 with removable end ferrul'es 3, and an inner cartridge-4 containing a. fusiblelinku .The outer casing 2 is preferably cylindrical in shape and made of some's'trong and nonconducting material such Vas fiber. A side openingy that vis disposed -intermediate the ends,=is provided-with a window 7 of glass or other suitable transparent material,.for a purpose hereinafter specified. The end ferrules 3 are made of spun brass or a suitable equivalent and are adapted to engage suitable clips in a fuse block. (not -shown Each fer-rule is provided with a plurality of side openings 8 `to receive screws 9:and 10. =A disk 11, substantially U-'shape in formyandfhaving a plurality of arms 12, is transversely disposed within the outer end of each ferrule 3 and isprovided with an integral stationary :jaw 13, and a movable jaw 14 which are adapted to grip the projecting end of the fuse link 5, when acted upon by the screw 9. The jaw 14 is adapted :for translative movement by means of a 'transversely disposed pin 15 rigidly associated with said jaw and working in a plurality ofoppositely disposed slots i16'in the arm. 1210i the disk 11. Aring 17 is -disosed within 'eachend of thecasing 2 and 1s provided with a .plurality of openings that are threaded 4to yengage the screws 9 and 10. The ring 17 is thereby forced outwardly against the casing and 4tends to tighten theengagement of the casing and the ferrule 3.

The inner cartridge 4 comprises. @Bf 6.17.1' .A

'same 'capacit-ies as before.

relop 18, the inclosed fusible-link 5, a body of incombustible powder 19, and a label 2U disliosedaaround said envelop. The link 5 and'powder 19 are old and well known in' the 'art and need not be further described. The envelop 18 preferably consists o if a closed cylinder of liber or similar material having one portion 21 crimped to reduce the Ldiameter, an'd the label 20 is disposed around said crimped portion. The label is provided with a plurality of spaced perforated lilies 22, and' it is glued to the envelop 18 between these lines only, although closely titting said crimped portion elsewhere. The voltage and current ratings of t-he fuse, as hereinbefore indicated, are printed on the label Q0 near the perforated lines 22, and

`are disposed opposite the window 7 in the casing 2, as indicated at 22B. The ends ot the fusible link 5 severally extend beyond the ends of the envelop 18 and are adapted to be held by the jaws o1"- the ferrules 3, as hereinbefore described.

Inv Figs. 5, 6 and 7, the body of the fuse is'the saine as that just described, but the end ferrules Q4 are provided with knifebladc contact members 26 for engagement with switch jaw-s on a fuse block (not show-n).l Each ferrule 24e is provided with a slot 25 through which the knife-blade conv=`tact member 2G projects.

Integral with the member 2G, and o'set a little .to properly eng-agethe-insible link 5, is a stationary 27: =A disk 9.8, disposed transversely within the out-er end of the ferrule :24 serves as anadditional support for the combined Contact member 26 and stationary jaw 27, and is provided with a countersunk'slot 29 -or l:i1-purpose to -be' described. A movable AView 30 is disposed to cooperate with said stationary jaw Q7 for gripping the exposed end of the fusible link 5. A pin 31 is rigidly 'associated with said movable jaw to work 'within the countersunk slot 29 when acted Aupon bythe screw 9. The expansion ring-1i? and the screw.- 10 are used in the Assl'nning-'the protective device ,tobe connected in an electrical circuit and that a. dangerous overload current suddenly flows through the line, the operation of the device is as follows: Thel fusible link- 5 ruptures,

presumably near its middle and narrowest section',` thereby opening the circuit. The explosive action causes 'the reduced portion *2,1l 'o f thev envelop 18 to expand, :thereby break-ing the' label 20l on one or both of the 'perforated Vlines 22 and 'clearly indicating 'that't'he fuse/laas blown.

'To "p'ut' theprotective device in operative 'conditionagaim one'end errule'is removed, fthe olld'cartridgge taken. out and 1anewone 's'li-'ppedfi-n, che e'nds of? the :Euslble luik being clamped within the jaws associated with the It'will be understoodthat modifications of the protective device'hereinbefore described may be made within the spirit and scope of my invention, and I desire that only such' limitations shall be imposed as are indicated in the appended claims.

l claim as my invention:

1. A protective device for electric circuits embodying an incasing member'ha'vig a windoivthereima yieldable renewable memher having a portion of reduced cross-section adapted for insertion therein and comprising a fusible body andassociated incombustible material, and means disposed-monolith@ portion of reduced crosssection that is adapted to burst upon the rupture of the fusible body. t

2. A fuse device comprising a yieldablo tusecarrying member, and a band of paper disposed around a .portion of the yieldable fuse-carrying member adapted .to burst upon the expansion of the said fusefcarrying inemher when the fuse is ruptured.

A fuse device comprising-a yeldblv fuse-carrying memberhaving its central portion reduced. in size, a band' of paper so disposedwith. respect. t0 .thflflud PQTQD of thev use-carry-ingfignernher. that .it ruptures when the fuse blowst 4. A protect-hie .device for electric circuits embodying a yieldable .ruse-Carrying member having one :portionireduced in size, a signal band :disposed around the said reduced portion to he set by the expansion of said reduced portion when the fuse is ruptured, and means for connecting said yfuse in said circuit..

5. A protective device forati electric circuit Campesina a .-yeldable fase-carrying .member having one portlonreduced in size,

a band of fragileniaterial attached to reduced portion and adapted to. burst upon the expansion of .the Said reduced portion when the-'fuse is ruptured. Y' i,

-A-A rretective 'device for electric circuits embodying a yeldable freeware/angine?" ber having Aone. partiva-.reduced 11n size, e band .uf-fragile materialatta-ehrd. .t0 Said duced perdon which. bursts apen .expansion of said portion-by .reason of the rupture of Said fuse, and. means. for ecneectingsad his@ in said circuit.

7. A protective device for electric circuits-embodyinga yieldable cartridge. .Carrying a fuse and having one portion reduced in Size, a band fit-Paper nartelfly attac-lied t0 Said reduced Portion. which beasts. uren.4 errnsin -Gf- .Said retti-Qa by. reirse the rupture Gfsaid inse, @crimenes for @91.1-

and adapted to burst when the cartridge yields upon the rupture of the fuse.

9. Ina protective device for electric circuits,fthe combination with an outer protec -tive casing having a Window therein, of an indicate by bursting when the fuse is ruptured.

l1. In a renewable fuse, the combination with a cartridge member having a window therein, of a renewable yicldable fuse-carrying member inserted therein and having one relatively short portion of reduced diameter, and a band of fragile material attached to said reduced portion that will burst upon expansion of the said reduced portion by reason of the rupture of said fuse.

In testimony whereof, I have hereunto subscribed my name this 26th day of April,

EDWIN H. GILBERT. Witnesses:

J. \VALTER MILES, B. B. HINES.

Copies ot this patent may be obtained for five cents each, by addressing the Commissioner of Patents, Washington, D. C. 

